- Lived:
- Jagannātha 1652–1744, born into a Maharashtrian Vedic family, working life at Amber and Jaipur; Jai Singh 1688–1743, born at Amber, king of the Kachhwaha state from 1699, builder of Jaipur, dead there in 1743 — the paṇḍit outlived his king by a year
- Field:
- astronomy, mathematics, statecraft and city-building — a Sanskrit scholar and a Rajput king running one scientific programme between them
- The Big Idea:
- Knowledge has no single homeland. A paṇḍit in his fifties learned Arabic and Persian to carry Euclid and Ptolemy into Sanskrit, coining over a hundred words to do it; his royal student built five giant masonry observatories and a planned city on the argument that when theory and observation disagree, the observation wins.
- In their words:
- "Since instruments of brass wear at their axes and shift in their circles, instruments of stone and lime were raised — immovable, of great radius — so that the divisions might grow large and the error small." (the reasoning of the observatory programme, as the Zīj-i Muhammad Shāhī's preface and Jagannātha's instrument chapters give it; our free rendering)
- If you remember one thing:
- Every schoolchild is taken to the Jantar Mantar; almost none is told the name of the astronomer behind it or the reasoning inside it — and the reasoning is the treasure: measure the sky yourself, at the largest scale you can build, and let no book, however famous, overrule what you see.